2017 AR4 is an asteroid in the Apollo orbit class. Its orbit takes it from 0.93 AU to 1.12 AU from the Sun; one orbit takes 378.7 days. Orbit from the JPL solution of 15 April 2021.
Where is it now
- Distance from Sun
- 1.016 AU
- True anomaly
- 270.15°
- Distance from Earth
- 1.907 AU
- As of
- 3 November 2026
Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.
In the sky
- Right ascension
- 15h 53m 52s
- Declination
- -18° 22′ 39″
- Constellation
- Libra
- Distance from Earth
- 1.91 AU
- Elongation from the Sun
- 18.37° — too close to the Sun to observe
Favours the southern hemisphere; low or below the horizon from far north.
From your location
See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.
Your location stays in your browser and is sent only for this calculation. Using a what3words address is optional; if you do, the three words go to what3words to be converted and we don't record them. Set a location first, then you can save an email alert for this object. See our privacy policy.
Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.
Orbital elements
- Semi-major axis
- 1.024 AU
- Eccentricity
- 0.0906
- Inclination
- 7.7°
- Orbital period
- 378.7 days
- Perihelion
- 0.932 AU
- Aphelion
- 1.117 AU
- Longitude of ascending node
- 104.98°
- Argument of periapsis
- 242.17°
- Epoch · J2000
- 2461200.5
- Orbit class · APO
- Apollo
- Earth MOID · 14.1 LD
- 0.0362 AU
- Tisserand (Jupiter)
- 5.956
Orbit quality
Orbit reasonably well determined (uncertainty code 4).
- Observations used
- 67
- Data arc
- 58 days
- First observed
- 27 December 2016
- Last observed
- 23 February 2017
- Residual RMS
- 0.55 ″
- Solution · Otto Matic
- 15 April 2021
Visual & observation
- Absolute magnitude (H)
- 24.8
Discovery & classification
Close approaches 63 on record
Top-down view of the ecliptic, Earth at the centre, for the 2042-06-01 07:29 UTC close approach of 2017 AR4. Catalogue miss distance 112.6 LD · 4.33 × 10⁷ km. The curve is the geocentric path from 2042-05-29 to 2042-06-04, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.
| When (UTC) | Body | Distance | Lunar distances | Relative speed |
|---|---|---|---|---|
| 2042-06-01 07:29:00 | Earth | 0.2892 AU | 112.6 LD | 11.8 km/s |
| 2043-06-18 21:02:00 | Earth | 0.076 AU | 29.6 LD | 6.1 km/s |
| 2044-03-26 14:15:00 | Earth | 0.1798 AU | 70.0 LD | 3.1 km/s |
| 2044-08-11 19:05:00 | Earth | 0.1207 AU | 47.0 LD | 4.4 km/s |
| 2045-01-12 16:02:00 | Earth | 0.1089 AU | 42.4 LD | 4.5 km/s |
| 2045-12-12 07:46:00 | Earth | 0.1122 AU | 43.7 LD | 6.6 km/s |
| 2046-12-13 15:42:00 | Earth | 0.3203 AU | 124.6 LD | 12.7 km/s |
| 2070-05-23 22:14:00 | Earth | 0.4419 AU | 172.0 LD | 16.2 km/s |
| 2071-06-05 15:11:00 | Earth | 0.2251 AU | 87.6 LD | 10 km/s |
| 2072-06-26 11:28:00 | Earth | 0.037 AU | 14.4 LD | 5 km/s |
Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.
Sources
- visual properties: JPL SBDB (lookup)
- orbital elements: JPL SBDB